Heating apparatus for aircraft or the like



W. E. HUFFMAN ETAL Original Filed June 6, 1935 HEATING APPARATUS FOR AIRCRAFT 0R THE LIKE Nov. 25, 1941.

Patented Nov. 25, `19461 HEATING APPARATUS FOR AIRCRAFT R THE LIKE William E. Huffman and George W. Replogle,

f Dayton,`0hio Original application June 6, 1933, Serial No.

Divided and 'this application October 10, 1939, Serial No. 298,806

(Granted under the act of March 3, 1883,V as amended April 30, 1928; 370 0. G. 757) 13 Claims.

The invention described herein maybe manufactured and used by or for the Goverment for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to apparatus for heating the interior of a vehicle body, such as cabins of aircraft, automobiles, and the like. The device relates particularly to a vapor heating system in which a vapor generator is operatively associated with `the exhaust system of the internal combustion engine driving the vehicle, to utilize the heat from the exhaust gases for operating the generator. The generated vapor is passed through a suitable radiator placed in the interior of the vehicle. 1

It is an object of this invention to provide a vapor heating system of a non-pressure type, in which pressure or heat-controlling devices are not required and in which the rate of Vapor generation is controlled by automatically varying the quantity `of liquid in the generator instead of varying the quantity of heat to the boiler.

It is a further object of this invention to pro-` vide a heating system in which `the quantity of liquid in the boiler is continuously and automatically reduced or totally 'displaced by vapor when a greater quantity of vapor is generated than can be condensed by the radiator. l

A further object of this invention is to provide a low pressure vapor generator associated with the exhaust manifold of the internal combustion engine of the vehicle, a radiator unit operatively connected to the generator for effecting a forced radiation of heatreceived therefrom, and a cony densing unit operatively connected'to the radiator and the generator for the purpose of oondensing' vapor yfluid received from the radiator/ and permit the return ow of condensed liquid into the generator.

` A still further object of this invention is to provide in a vheating system ofk this character, a radiator having meteringv means so located with respect thereto that as liquid in the boiler is heated to the boilingpoint and passed intothe radiator, it is permitted to pass into the condensing unit in al prearranged controllable amount. This permits the forcing of liquid from the boiler into the condenser when suiiicient back pressure has been built upl in the radiator to overcome the staticl head in the condenser. It is This application is a division of application Figure 1 of the drawing diagrammatically illusf trates a generator, radiator, condenser, and appurtenant structure.

Figure 2' is a sectional view from the left through the exhaust pipe showing an elevational end View of the boiler;

Figure 13 is a modied type of boiler; Figure i is an end view of Figure 3. Referring to the drawing, B refers generally to the boiler or generator; C, to the condenserpossible, by thus utilizing the back pressure,` to

force all the liquid from the boiler, thus automatically permitting only sufficient liquid to remain in the boiler to generate the amount of steam required. y v

reservoir unit; and R, to the radiator.

The generator'is operatively connected to the radiator by tube I5'. The condenser is connected to the bottom of the radiator by tube 51 and to the top of the radiator by tube I6'. The condenser-reservoir unit is communicatively connected tothe generator by tubes l1, 29 and passageway 28.l

Generally speaking, heat conveying vapor isV generated in the boiler and conducted'to the radiator placed in the interior of the compartment to be heated. l'I'he condenser and reservoir unit functions to maintain` a supply of fluid to the generator and to receive condensate fluid from the radiator when the radiator becomes lled with steam or vapor under pressure. The condenser unit also functions to prevent escape of vapor and acts as a relief valve to prevent the building up of a dangerous pressure. y V

The generator B comprises a member I8 inserted in andconnected to an exhaust line I9.

Contained within member I8 is a boiler or generator 2| in the shape of a wedge having parallel, generally triangular-shaped faces and `a base in uppermost position. The lower portion of the wedge comprises a reservoir 22'for the unvaporized fluid anda p1ug`2' for emptying the reservoir. Overflow tube 2l, controlled by valve 25, serves to control the level of uid in the generator.

The generator 1s providedwitn a p1uggea mung inlet 23; an opening 2l for allowing passage of vapor from the generator to the radiator; a tube 21 for returning the condensed vapor from tube `I5 directly to the reservoir; and a tube 29 having an opening portion 28 operatively engaging tube l1 for directly connecting the condenser with the reservoir portion of the generator.

55 The condenser and reservoir unit C is provided with a reservoir portion I2; a condenser portion I2'; a spring operated nap valve 53 adjacent the bottom of the reservoir portion and adapted to open upon a predetermined pressure difference; a vent 45 adjacent the top of the condenser; and a by-pass line 56' having therein apre-calibrated spring controlled check valve 52.

The radiator R. comprises the usual radiating fins II and heat-distributing fan 59 in addition to the header tank or sump 34'. Valve 5| in sump 34 comprises ball valve 56, upper valve seat 54 and lower valve seat 55.

The header tank is provided with a member 36 having. valve seat 54 and openings 35. Open-l ings 35 permit equalization of pressure between the sump and radiator and prevents ball 56 from sticking in the closed position. Adjacent the upper end of the radiator is a valve 46 for permitting the flow of uncondensed steam to the condenser and also for the purpose of providing an outlet for air which may have been trapped in the radiator. The valve seat serves as a metering orifice to regulate the return of uncondensed steam directly to the condenser unit.

In the operation of the device, heated vapor -generated in the boiler 42| by the hot gases from exhaust pipe I9 passes through opening 21 and tube I to sump 34 and thence into the radiator through opening 54. Valve means 46 maybe closed or may be opened to permit iiow to the condenser of any air that may have been trapped in the radiator and also to permit the return of a-metered amount of uncondensed vapor directly to the condenser. rI'he hot vapors are condensed in the radiator and the condensate will collect in the sump 34' until the sump is full, at -which time ball valve 56 will seat in opening 54, preventing condensed liquid from being forced up into the radiator. porarily closed off continued heating of the vapor will establish a pressure which will force the condensed fluid in the sump into the -pipe 51 toward the condenser unit. This lowers the ball 56,

v allowing more steam to enter the radiator and valve 53 prevents,l return of fluid directly to the condenser and permits the building up of suflicient pressure to force the condensate from the sump 34 through conduit 51 into the condenser.

The nature of construction of the valve 56 and seat 55 is such that vapor under pressure will force past valve 56 to conduit 51 to force the condensed fluid fromsump 34 through tube 51 into condenser unitC.

Sump inlet I3' is now tern- In order to prevent the generator unit from -standing with condensate in the radiator sump,

trated in Figures-3 and 4. As shown in these figures, this boiler is provided with a circular portion 66 forming an inner casing which is adapted to be connected to the exhaust manifold of the engine. An outer casing 61 of cylindrical cross section and forming a main boiler in adapted to be suitably Welded or otherwise secured to the inner portion 66 of the boiler. By observing Figures 3 and 4 it will be noted that an auxiliary boiler unit 68 is provided which is mounted within the inner circular casing 66 of the boiler heretofore mentioned. This auxiliary boiler is connected at its upper and lower end to the main boiler 61 through the medium of connecting lines 69 and 10. As shown in Figure 4 this auxiliary boiler is comparatively small in cross sectional area; consequently, the amount of water retained therein is substantially small. By providing an auxiliary boiler in the manner set forth', it will be apparent that when the motor is started the exhaust gases in passing around the auxiliary boiler will immediately heat the water in the boiler to boiling point and a generation of steam will be effected in a very short period of time.

The invention is not intended to be limited to the specic form shown in the drawing and described in the detailed description, it being understood that the invention is susceptible of various modifications and alternative constructions that fall within the spirit and scope of the invention as expressed in the appended claims.`

^ We claim: f

. 1. In a heating system, a steam generator, a radiator including an inlet and an outlet orifice, the former having an effective cross-sectional area suiiiciently large to permit the steam to v :enter said-radiator i'n .quantities in excess of the condensing capacity thereof, means connecting said generator tothe'inlet oriiice of said radiator a condenser unit operatively connected to said generator and including a reservoir connected to fthe outlet orifice of said radiator and positioned above said steam generator and radiator for receiving and condensing the excess of steam from said radiator and permit gravitational flow of the same when condensed into said steam generator, the leffective cross-sectional area of said outlet orifice being less than the effective cross-sectional area of said inlet orice to restrict the passage of excess steam from said radiator and establish a back pressure therein, and iioat controlled means .cooperating 'with said radiator for obtaining a -I radiator including an inlet and an outlet orice,

the former having an effective cross-sectional area suiiciently large to permit the steam to enter said radiator in quantities in excess of the condensing capacity thereof, means connecting said generator to theinlet orifice of said radiator a condenser unit operatively connected to said genverator and including a reservoir connected to the outlet orice of said radiator and positioned above said steam generator and radiator for receiving and condensing the excess of steam from said radiator and permit .gravitational flow of the same when condensed into said steam generator, the eiective cross-sectional .area of said outlet orifice being less than the effective cross-sectional exhaust manifold of the engine is better illusarea of said inlet orice to restrict the passage of excess steam from saidradiator and establish a back` pressure therein, and means in the lower -end of said radiator for automatically returning in successive stages the condensed steam in said area sufficiently large to permit the steam to enter said radiator in quantities in excess of the condensing capacity thereof, means connecting said generator to the inlet orice of said radiator a condenser unit operatively connected to said generator and including a reservoir connected to the outlet orice of said radiator and positioned above said steam generator and radiator for receiving and condensing the excess of the steam from said radiator and permit gravitational iiow of the same when condensed into said steam generator, the effective cross-sectional area of said outlet orifice being less than the eifective crosssectional area of said inlet oriiice to restrict the passage of excess steam from said radiator and establish a back pressure therein, the lower end Y condenser unit.

4. A radiator including a core through which a heating fluid is caused to travel, an upper and a lower header on the opposite end of said core, the upper header including an outlet orifice, the lower header being provided with an inlet orifice, a manually adjustable metering device in said outlet oriiice for restricting, in yprei'letermined amounts, the passage of the heating nuid therethrough, the lower header being provided with an auxiliary port to permit the discharge therethrough of the condensed heating fluid and a ball check valve for controlling the opening and closing of said port.

5. A vapor generator comprising, a casing adapted for being connected with the exhaust pipe of an internal combustion engine, a boiler ing, an inner casing within said outer casing adapted for being connected to the exhaust pipe of an internal combustion engine, the effective cross-sectional area of said inner casing being substantially equal to the effective `cross-sectional area of said exhaust pipe to receive a maximum 9. 'A vapor generator comprising an outer casing, an` inner casing within said outer casing adapted for being connected to the exhaust pipe of an internal combustion engine, the eifectivcf cross-sectional area of said inner casing being?,

substantially equal to the effective cross-sectional' in said casing within which a liquid to be evaporated is received, said boiler being in the form of a wedge with two parallel, generally triangular-shaped faces and a base in uppermost position, the lower portion of said boiler constituting a sump portion, an outlet pipe for the evaporated liquid located adjacent the vupper portion of said boiler, and an inlet pipe having its lower end disposed in the sump of said boiler.

6. A vapor generator as set forth in claim 5, the sump portion of said boiler being characterized by being disposed outside the zone of heat of said casing to prevent surging of liquid discharged through said inlet pipe and thereby stabilize the level of the liquid.

7. A vapor generator comprising, a casing adapted for being connected to the exhaust pipe of an internal combustion engine, a boiler in said casing within which a liquid to be evaporated is received, said boiler being provided with ay sump area of said exhaust pipe to receive a' maximnm of heat therefrom, the outer casing/ forming a. main boiler within which a liquid tobe evaporated is adapted for being received, and an auxiliary boiler communicatively` connected to said first mentioned boiler and disposed within said inner casing. the heating surface of said auxiliary boiler being small as compared to the heating surface of said outer casing to thereby obtain an instantaneous generation of the vapor of .the liquid contained therein.

10. In combination, a vapor generator adapted to receive a vaporizable fluid and associated with the exhaust pipe of an internal combustion en gine to be heated by the exhaustgases passing therethrough, a reservoir above said generator and communicatively connected therewith, a oneway valve for controlling iiow of fluid/from said reservoir to said generator, a radiator below said generator, a condensate collecting chamber communicatively connected with said radiator and in series with said generator and said reservoir and valve means in said chamberv operatively as-` 4 sociated with the connection of said chamber and radiator and responsive to the condition of the fluid in the chamber for controlling the ilowand condensate to said means communicatively connecting said generportion at its lower end, an outlet pipe for the 8. A vapor generator comprising, an outer casator to said radiator for the passage of vapor,

thereto, condensate receiving means communicatively connected to said radiator andto saidv condenser-reservoir unit and means operatively associated with said condensatereceiving means and responsive to the accumulation of a predetermined amount of condensate in said condensate receiving means for controlling return ol condensate tosaid condenser-reservoir unit.

12. A vapor heating system for a vehicle driven by an internal combustion engine comprising a vapor generator adapted to contain a vaporizable liquid and associated with the exhaust pipe oi said motor so as to be heated by the exhaust gases passing therethrough, a radiator positioned in said vehicle with the lower portion thereof below said generator, a vented condenser-reservoir unit operatively connected to said generator for supplying vaporizable uid to said generator, valve means in said condenser-reservoir unit for preventing return of liquid andfor vapor from said generator to said condenser-reservoir unit, pressure relief means associated with the connection between thegenerator and the con-- denser-reservoir unit, conduit meansl for conveying vapor from said generator to said radiator, sump means communicatively connected with said condenser-reservoir unit and operatively assaid motor so as to be heated by the exhaust gases passing therethrough, a radiator communicatively connected with said generator and positioned in said vehicle `with the lower portion of said radiator below said generator, a vented condenser-reservoir unit communicatively connected with said .generator and said radiator for supplying fluid to said generator and receiving condensate and/or vapor from said radiator, valve means in said condenser-reservoir unit for preventing return o'f liquid and/or vapor from said generator to said condenser-reservoir unit, pressure relief means associated with the connection between the generator and the condenser-reservoir unit, condensate accumulation sump means associated with saidradiator, conduit means connecting said generator with said sump means for conveying vapor to said radiator, valve means in saidvsump means operative upon the accumulation of a predetermined amount of' condensate in said sump means to prevent flow of vapor to said radiator thereby enabling vapor pressure to re- 

